Bears on the move in the Finger Lakes

The months of June and July are when black bears mate–and it’s the only time of year when males and females associate with one another. The female, known as a sow, comes into estrus every other year after dispersing the cubs that have lived with her for the previous year-and-a-half. She is promiscuous and will mate with more than one male, or boar. Through a curious phenomenon called delayed implantation, her eggs will not become fertilized until she dens again in the fall. Anywhere from one to five cubs could subsequently be born in late January or early February of the next year–depending on how many times she has been bred–and each one could potentially be the offspring of a different sire.

The months of June and July are also when you might see an increase in daytime black bear activity. One of the reasons is because they are mating but another has to do with the dispersal of adolescent cubs. After 17 or 18 months of motherly love, the sow gives her babies a swat and chases them away so that she can mate again. Since black bears are not inclined to share territories, the swats and chases continue while they wander in search of territories of their own, which is how they sometimes turn up in the most unlikeliest of places. I took this photo from my deck on a rainy day several years ago when a sizeable boar was pursuing an estrus sow through my yard. The missing fur on her rump is an indication of how many times she had been bred.